Three previously unknown (and unfinished) sketches by celebrated 20th-century artist Amadeo Modigliani were discovered at the University of Haifa’s Hecht Museum, hidden beneath the surface of one of his paintings. His works were X-rayed prior to an upcoming exhibit in Philadelphia.

https://www.timesofisrael.com/three-3-hidden-modigliani-sketches-found-under-painting-at-haifa-museum/